We are sorry to hear stains appear on the outside of your stainless steel pan. There can be different reasons for this. Luckily, most of the time, these stains can be easily removed.
Reason
The outside of the pan may become discoloured due to overheating and corrosion by salts and minerals.
The exterior of the pan can start to exhibit traces of use relatively quickly. One reason for this could be overheating. This happens when a pan is heated suddenly over a very high heat, without the heat then being reduced. The pan may take on a golden shine. This will not affect the pan’s performance, though.
Another reason is when grease residues come into contact with the exterior of the pan. If your pan is still (very) hot when this happens, the grease may leave a charred layer on the stainless steel.
Using a dishwasher or any associated abrasive products can also result in discolorations along the rim of the pan. The rim may then lose some of its shine.
Solution
This discoloration can be removed with a stainless steel cleaner. This cleaner will not affect the performance of your stainless steel products.
If option 1 does not work, then the best thing you can do is try to remove the stains with a melamine wonder sponge and some dishwashing liquid.